Add OLED driver function to determine if the screen is currently on (#10382)

drivers/oled/oled_driver.c

@@ -534,6 +534,8 @@ bool oled_off(void) {
     return !oled_active;
 }
 
+bool is_oled_on(void) { return oled_active; }
+
 // Set the specific 8 lines rows of the screen to scroll.
 // 0 is the default for start, and 7 for end, which is the entire
 // height of the screen.  For 128x32 screens, rows 4-7 are not used.

drivers/oled/oled_driver.h

@@ -257,6 +257,10 @@ bool oled_on(void);
 // Returns true if the screen was off or turns off
 bool oled_off(void);
 
+// Returns true if the oled is currently on, false if it is
+// not
+bool is_oled_on(void);
+
 // Basically it's oled_render, but with timeout management and oled_task_user calling!
 void oled_task(void);